Opera House Sydney : Which are the "true" dates?

Question

I went on various sites and the problem is: the dates do not correspond!! Say me what a are true! please 1) When have really to begin the joists? in 1965 or 1958? 2) Is Jorn Utzon withdrawn in 1966? 3) does inauriguration have it had the 20 or on October 23?

ps I'm a french, sorry for the orthography

Answer 1

Sydney Opera House

1. Construction of the building commenced 5th December 1958, and proceeded in three stages over the next fourteen years.

STAGE 1: PLATFORM: 1958-1963 (Architect: Jørn Utzon)  

STAGE 2: ROOF: To Feb 1967 (Architect: Jørn Utzon)  

STAGE 3: INTERIOR: To June 1973 (Architect: Peter Hall)

2. February 28, 1966 Jørn Utzon resigned.

In mid 1965 a new Liberal government was elected in the state of NSW. The Minster of Works Davis Hughes began questioning Utzon's designs, schedules and cost estimates and eventually stopped payments to Utzon who was forced to withdraw as chief architect in February 1966.

3. The Opera House was formally opened by Elizabeth II, Queen of Australia, on 20th October 1973.

http://www.gids.nl/sydney/opera.html